最新刊期
期 2 ， 2019
- 摘要：Temperature field analysis through finite element model is important in the study of clutch design and control. The frictional heat model is the key to the calculation accuracy of temperature field. Aiming at the two main frictional heat flux models of heat flux uniform distribution and pressure uniform distribution，they are applied to FEM thermal analysis model of clutch respectively to calculate the temperature field varying process with time and space under the extreme condition of continuous sliding. Their results are compared in terms of the maximum temperature, temperature distribution and temperature gradient along the radial direction. In addition, the scope of application of the two models is given.关键词：Dry clutch;FEM thermal analysis;Heat flux;Pressure uniform distribution model;Heat flux uniform distribution model
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发布时间：2022-10-09 - 摘要：The stress intensity factor is an important parameter to study the fracture problem. The occurrence and development of gear cracks can be measured and controlled， which is of great significance for studying the fatigue damage of cracks and predicting life. In order to study the variation law of three-dimensional crack stress intensity factor of spur gears， a three-dimensional finite element model with initial semi-elliptical cracks is established by Abaqus software. The stress intensity factor of the semi-elliptical crack front is calculated， and the influence of crack size， shape and load variation on the stress intensity factor at the leading edge is analyzed. The results show that the cracks of the roots of the teeth mainly manifested as open cracks during the expansion process. As the load increases， stress intensity factor KI also increases， but its distribution rules remain unchanged. With constant load， KI increases with the increase of crack size. In the establishment of semi-elliptical cracks， as the long axis increases， the KI fluctuations on the crack front gradually become smaller.关键词：Stress intensity factor;ABAQUS;Crack propagation;Finite element model
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发布时间：2022-10-09 - 摘要：Two pairs of hypoid gears with 7/37 and 8/41 teeth are selected as experimental objects. The ultrasonic lapping of gear is carried out on the modified rolling inspection machine Y9550， ultrasonic vibration frequency is 16 kHz， ultrasonic grinding time is 3 min. Then the JD45+ measuring machine is used to measure the deviation error of 45 points on the tooth flank before and after ultrasonic lapping， and then the helical angle or pressure angle error are calculated by the tooth flank error in the direction of tooth length or tooth height. Finally， the tooth flank error， spiral angle error and pressure angle error before and after vibration processing are compared. The results show that ultrasonic vibration lapping gear can eliminate gear flank error， improve the position and shape of gear contact area， improve gear tooth flank smoothness， improve gear machining quality， but also can′t be excessively lapping.关键词：Hypoid gear;Ultrasonic vibration;Lapping gear;Tooth flank quality
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发布时间：2022-10-09 - 摘要：Through the analysis of tractor fuel economy index and the influence factors of tractor economical efficiency， a kind of fuel economy shift rule with tractor minimum fuel consumption and traction as the goal of most efficient is put forward. According to the optimal fuel economy of the tractor， combined with the structure and transmission characteristics of the hydraulic mechanical continuously variable transmission（HMCVT）， the requirements of realizing the fuel economy of the tractor are expounded. A kind of shift rule with optimum economical efficiency of HMCVT is explored， which taking ratio of engine fuel consumption to transmission efficiency of HMCVT is the smallest as the objective. By using the SimulationX， the simulation is carried on， it is concluded that the engine speed torque curves under various gear， through compared with outside the engine characteristic curve， can make all the gears are at the lowest fuel consumption economy area， and guarantee the stability of the speed of the tractor， conforms to the economical shift rule.关键词：Tractor;Fuel economy;Hydraulic mechanical continuously variable transmission;Shift law
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发布时间：2022-10-09 - 摘要：Since the state of operational performance of gearbox proper on the guarantee for smooth of entire device， it is quite significant to monitor and evaluate comprehensively its state of operation. Owing to the limitations of index weight determination in traditional state evaluation method， the entropy model modified G1 is innovatively introduced to scientific and reasonable weight， the concept of relative health degree is proposed， and the grades of health state are classified based on the healthy values to quantitatively describe the running state of gearbox. The analysis of the gearbox fault in certain petrochemical company shows that， this method has better effective in evaluating the gearbox running status， it can provide a theoretical basis for the maintenance based on state.关键词：Gearbox;Relative health degree model;Entropy-revised G1 method;Comprehensive evaluation
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发布时间：2022-10-09 - 摘要：An improved quintic polynomial interpolation method is proposed to solve the catastrophe phenomenon caused by the original method order in the course of solving the motion trajectory of the robot. The ER 3A-C60 industrial robot produced by a company is taken as the research object. Using the standard D-H parameter method， the coordinate system of the robot connecting rod is established first， then， the robot simulation model is created and the kinematics forward solution and inverse solution are solved， the workspace point cloud image at the end of the robot is also been made. In the process of solving robot motion trajectory， a fusion method of polynomial interpolation and B-spline interpolation is proposed to eliminate the catastrophe phenomenon. The experimental results show that the optimized joint correlation curve is smoother， the mutation phenomenon is eliminated， and the impact of vibration and shock on the performance and life of the robot is avoided.关键词：Standard D-H parameter;Trajectory planning;Quintic polynomial interpolation;B-spline interpolation
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发布时间：2022-10-09 - 摘要：At present，the domestic caliper logging tool adopts an eccentric circular arc type in the pushing arm， which has the problems of large dynamic load， poor force transmission effect， and short instrument life. In order to solve the above problems， the three kinds of structural schemes of involute， Archimedes spiral and eccentric circular arc are used for parametric design of pushing arm， and the three kinds of pushing arm cam motion characteristics and mechanical efficiency are analyzed. The analysis shows that adopting the involute pushing arm structure in the split pushing system can greatly improve the force characteristics of the piston rod， reduce the friction and wear， and further improve the measurement accuracy. The ADAMS/View module is used to create three types of split pushing systems to open and measure models， the initial parameters are set and motion simulation is performed. The trajectory curves of piston rods in three motion states are obtained， and their motion laws are verified， which provides a theoretical basis for the optimal design and performance improvement of the structure of caliper logging tool.关键词：Caliper logging tool;Split-type push-back system;Profile;Parametric modeling;Motion simulation
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发布时间：2022-10-09 - 摘要：In order to improve the road adaptability of urban sanitation sweeping vehicle， a hydraulic mechanical compound transmission device is designed. The transmission device has three working modes of pure hydraulic pressure， torque splitting speed and speed splitting moment. The theoretical analysis of speed regulation characteristic， power shunt characteristic and efficiency characteristic is carried out， the simulation of hydraulic mechanical compound transmission device is carried out by using AMESim software. The simulation results show that different load torque has little effect on output speed. The experimental study on the prototype of hydraulic mechanical compound transmission device is carried out through building test bench and the stepless speed regulation curve and efficiency curve are obtained. The test results show that the designed hydraulic mechanical compound transmission device for the sweeping vehicle has the advantages of stable transmission and high efficiency， and can better meet the needs of the urban sanitation sweeping vehicle under various working modes.关键词：Sweeping vehicle;Hydraulic mechanical compound transmission;Mode;AMESim;Test
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发布时间：2022-10-09
Theory·Reserach
- 摘要：A kind of 2RRPaR+PPaP three translational space parallel mechanism is designed, and the forward and inverse position solutions equation and Jacobi matrix of the mechanism are derived. The optimization mathematical model is set up with the optimization goal of workspace and global dexterity. Based on the maximum number of scatter points in the workspace and the maximum dexterity, the differential evolution algorithm is used to optimize the design and get the optimal parameters of the mechanism. By comparing the workspace and dexterity of the mechanism before and after optimization, the results show that the motion performance of the optimized mechanism has been greatly improved, which laid the foundation for the design and application of the mechanism.关键词：Parallel mechanism;Workspace;Dexterity;Differential evolution algorithm;Optimization design
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发布时间：2022-10-09 - 摘要：In order to enhance the performance of fighter， and realize the aim of lightweight design of aircraft gun， taking the transmission gear of a certain aircraft gun ammunition box as the research object， through topological optimization method of material interpolation model based on SIMP（solid isotropic material with realization）， a topological optimization mathematical model for the density of gear structural unit as design variable， minimum flexibility as objective function， the percentage of volume fraction before and after optimization and the structural balance equation as constraint functions is established， the topology optimization of ammunition box transmission gear is studied. Depending on the result of topology optimization， the gear structure improvement and statics analysis are carried out. The analysis results show that the optimized gear structure is reduced by 15.4%， maximum deformation is reduced by 14.2%， maximum stress is increase by 20.8%， and the gear structure lightweight design is achieved under the condition of satisfying the rigid strength of the structure and keeping the feeding principle unchanged. It has engineering application value for gear structural weight reduction， and provides the reference for other parts lightweight design.关键词：Transmission gear;SIMP material interpolation model;Topological optimization;Checkerboard;Light weight
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发布时间：2022-10-09 - 摘要：In order to improve the track symmetry of carbon-free car for ‘S’ shape， the movement mechanism of the car is designed， the mathematical optimization model of the steering mechanism is built， and the relevant parameter is optimized by using the Matlab Optimization Tools， the influence between parameter and track symmetry is discussed. The accuracy of the optimized parameter is confirmed by ADAMS simulation， the track symmetry achieved 96% theoretically. The test shows that the car can avoid 20 obstacles which verified the rationality of the mechanism.关键词：Carbon-free car;Steering mechanism;Optimization tools;Adams simulation
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发布时间：2022-10-09 - 摘要：A type of stepless speed regulation device is designed based on the differential gear train and hydro-viscous speed regulation theory， and the main parameters of the planetary gear set are determined， then transmission structure is designed in SolidWorks software. In order to verify the performance of system speed regulation， a co-simulation is carried out with AMESim and MATLAB/Simulink， the physical model of speed regulation system is built in the AMESim software， the controller is designed in MATLAB/Simulink. Furthermore， in order to improve control performance， the way of combining fuzzy controller and PID controller is proposed. The results of the study show that， the system speed regulation under the fuzzy PID control is more stable， the adjustment time and static error decrease by 25% and 67% respectively compared with traditional PID.关键词：Differential gear train;Hydro-viscous speed regulation;Fuzzy controller;Co-simulation
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发布时间：2022-10-09 - 摘要：In view of the simple structure of the robot in the current market and the fact that each joint is driven by a servo motor， a humanoid robot with a dodge function is designed， which is driven by a single motor and controls the state of the electromagnetic clutch to realize the movement of the lumbar joint. And finally the dodge motion of robot is completed. In order to verify the correctness of the main component selection and the rationality of the structural design， the dynamics of the robot trunk structure is studied by using the Lagrangian Function， and then the dynamics simulation analysis of the robot virtual prototype is performed by using ADAMS software， the corresponding joint torque curve is obtained. Finally， the robot physical assembly is completed and the dodge function is verified through experimental test.关键词：Dodge function;Humanoid robot;Lagrangian dynamics;Adams
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发布时间：2022-10-09 - 摘要：In order to solve the difficulty in climbing stairs for the elderly and disabled， a new type of combined climbing wheelchair with planet wheel track is proposed. The combined structure with planet wheel track is used to achieve the function of stair-climbing and obstacle-surmounting. The wheelchair is driven by a motor， the planet wheel adopts chain drive to climb stairs and drive on the flat ground. Combined with the track device， this structure effectively reduces the vibration of the wheelchair with planet chair and improves the obstacle-surmounting ability of traditional wheelchair. On the basis of comparing the structural characteristics of the existing climbing wheelchair， the scheme of designing a new type wheelchair robot with a combination of with the planet wheel and track is introduced， and its operating principle is analyzed， a mathematical model is established to make a kinematics and dynamics analysis on the stair-climbing process. The results show that， the wheelchairs can safely climb most stairs. The structure design of the wheelchair is reasonable， the combination of climbing stairs and moving on the flat ground is realized.关键词：Planet wheel;Climbing wheelchair;Kinematics
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发布时间：2022-10-09 - 摘要：According to the requirement of the key technology research mission of on-orbit assembly space telescope and in order to implement the on-orbit assembly service effectively，the ground verification scheme of the on-orbit assembly robot and sub-mirror assembly sub-system is designed，the end grab mechanism of the assembly robot is designed and analyzed. The scheme of inserting grasp and expanding lock is adopted in the grasp mechanism，and the control system of the assembly robot is also described. After the calculation and analysis，this design can meet the application requirements of the on-orbit assembly space telescope during the ground verification phase.关键词：On-orbit assembly;Grab mechanism;Closed-loop control
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发布时间：2022-10-09 - 摘要：A new 5 degree of freedom parallel mechanism is proposed for the special case of 5 degrees of freedom， and its kinematics is analyzed. Using the spiral theory and the modified G-K formula， the degree of freedom of the parallel mechanism is verified， and the inverse kinematics of the mechanism is solved by the closed loop vector method. The kinematics simulation of the mechanism is carried out based on the Matlab and Adams. The degree of freedom of the mechanism and the inverse kinematics curve obtained by Matlab and Adams are obtained. The correctness of the degree of freedom of the mechanism is verified by Adams simulation， and the correctness of the inverse solution of the mechanism is verified by comparing the inverse kinematics curves of Matlab and Adams.关键词：5 degree of freedom;Parallel mechanism;Kinematics;Adams
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发布时间：2022-10-09
Design· Calculation
- 摘要：Based on the material structure thermodynamics and heat treatment commercial simulation software， combined with the heat treatment process of the driven gear of the actual vehicle final reducer， the heat treatment deformation of gears of 20CrMoH and 8620H materials are researched. Taking the driven gear of the final reducer as the research object， the performance database of 20CrMoH and 8620H materials is established by JMATPRO software， and the numerical analysis model of the gear carburizing and pre-cooling quenching process is established. By using DEFORM software simulation，the of heat treatment deformation information of 20CrMoH and 8620H gears is obtained. The research shows that， the carbon content and hardness of the 8620H gear surface are less than 20CrMoH material，compared with 20CrMoH， the 8620H gear heat treatment deformation is smaller and more uniform.关键词：DEFORM software;20CrMoH;8620H;Gear;Heat treatment deformation
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发布时间：2022-10-09 - 摘要：Based on the thermodynamics and dynamics analysis of polymer composite gear meshing transmission process, the coupling thermal-mechanical model is established, the changing rule of the gear body temperature rise and the transient temperature of friction interface is studied. The main factors influencing the temperature field distribution of molecular composite gear during gear meshing transmission are analyzed by using the finite element software LS-PrePost. The body temperature rise and instantaneous temperature rise are measured in real time by infrared thermograph. The results show that the greater the friction coefficient, the more significant the temperature rise of the body. With the increase of external G, the instantaneous temperature rise of the contact interface increases, and the theoretical calculation value is basically consistent with the measured value.关键词：Tribology;Thermodynamics;Body temperature rise;Instantaneous temperature rise
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发布时间：2022-10-09 - 摘要：In order to solve the spur bevel gear end meshing problem， through the straight tooth bevel gear profile modification， improve the small end of the oil film carrying capacity， making the distribution of load along the width of the tooth evenly. The second parabolic curve is adopted in tooth profile modification firstly， and then the height of the tooth edge trimming of the driving wheel and the driven wheel is changed. After determining the modification parameters， an elastohydrodynamic lubrication model is established for the straight line contact of the bevel gear with infinite line， the pressure and the film thickness are solved by the multigrid method， and the elastic deformation is solved by the multigrid integration method. The results show that the oil film pressure at the tooth point after trimming the edge is smaller than that of the original， and the oil film thickness becomes larger. After the second parabolic curve modification， the oil film pressure at the instantaneous point of engagement and instantaneous point of engagement is significantly reduced at the Hertz contact area. The oil film thickness in the Hertzian contact area increases significantly， the maximum oil film pressure on the grinding mesh distribution decreases， the minimum oil film thickness increases， the central oil film pressure decreases， and the central oil film thickness increases. Modification parameters affects the oil film pressure and oil film thickness after the modification， modification changes the load distribution in the direction of the tooth width， the load difference between the small end and the large end of the straight bevel conical gear is reduced， and the tooth surface load is transferred from the end to the middle of the tooth width. Tooth profile modification can improve the lubrication condition of the gears， increase the oil film pressure in the meshing process， reduce the friction and wear of the tooth surface， and at the same time avoid the occurrence of tooth surface glue.关键词：Tooth profile modification;Tip repair edge;Infinite line contact;Oil film pressure;Oil film thickness
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发布时间：2022-10-09 - 摘要：Based on the analysis of the physicochemical characteristics of nano-ZrO2， SiC， SiO2， and Al2O3， the vibration and noise characteristics of lubricating oils containing ZrO2， SiC， SiO2， and Al2O3 additives on helical gears are investigated. The current 20CrMnTi helical spur gears are tested. Routine lubrication and lubricity with nano additive lubricants are applied. By applying different loads and speeds to helical gears， the vibration and noise characteristics of helical gears under different working conditions and different lubrication methods are analyzed. Effect of nano additive lubricant on gear vibration and noise is analyzed. The results show that the nano additive lubricant can effectively reduce the vibration and noise values of the helical gear under different working conditions in a relatively short period of time， especially for the axial vibration reduction effect is more obvious than the radial direction. On the basis of this， the sensitivity of the gear damping effect to the load and rotation speed under the lubricant additive method of nano additive is further analyzed， and it is found that the nano additive lubricant oil has more sensitivity to the rotation speed of the gear.关键词：Nanometer;Additive;Gear;Lubricating;Vibration;Noise
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发布时间：2022-10-09 - 摘要：In view of the difficulties encountered in the study of the kinematics inverse kinematics of grasping manipulator, a ART-RBF model based on soft competition mechanism is selected. On the basis of traditional RBF neural network, adaptive control generates the number of hidden layer nodes, and the similarity soft competition is applied in the first stage of learning. Using the soft competition mechanism, each node of the hidden layer can be involved in the learning of the sample, the utilization rate of the node is improved, and the error of the sample in the inter class overlap can be reduced, and the prediction accuracy can be improved. Finally, the motion simulation of the manipulator is carried out by ADAMS, and it is compared with the forward kinematics solution to verify the correctness of the positive solution equation. The results show that the soft competition algorithm can improve the prediction accuracy to a certain extent. The simulation results show the accuracy of the positive solution data and provide the basis for the follow-up motion control.关键词：Manipulator;Inverse kinematics;Soft competition;ART-RBF;Motion simulation
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发布时间：2022-10-09 - 摘要：Taking the 3D model of spiral bevel gear built by CATIA through the secondary development as research object， the simulation analysis of spiral bevel gear is carried out by using Abaqus software， and the dynamic performance of spiral bevel gear under different loads is simulated. The contact analysis s conducted and the curve of transmission error is extracted. The results show that the fluctuation amplitude of gear transmission error decreases with the increase of load， but the deviation from the zero line increases. It indicates that the spiral bevel gear drives more smoothly with increased load， the transmission accuracy decreased accordingly.关键词：Spiral bevel gear;Dynamic performance;Transmission error;Contact analysis
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发布时间：2022-10-09 - 摘要：Hybrid machine tool is a combination of series， parallel mechanism and robotics，which contains the advantages of them and used more and more widely in the manufacturing equipment for parts with complex structure. A five-axis linkage hybrid machine tool is proposed， and the realization and principle of manufacturing process and principles are analyzed. Based on the constraint of rod length in parallel modules， the kinematics model in machining process is established. Based on the velocity projection， the Jacobi matrix of parallel modules is solved. The dynamics model of the machine tool is established which based on the Lagrange equations and Jacobi matrix. Finally， the theoretical analysis results are calculated by Matlab. The required machine driving displacement， speed and force is being solved in the case of known machine tool cutting amount. Combined with kinematics results， the machine tool workspace is analyzed. The results show that the hybrid machine tool has good kinematics， dynamics and large workspace and other performance， and can meet the complex parts processing， but also provide a theoretical basis for the development of hybrid machine tool.关键词：Hybrid machine tool;Parallel module;Jacobi matrix;Lagrange equation
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发布时间：2022-10-09 - 摘要：Taking a pure electric vehicle as the research object， the optimization of power system parameters is analyzed. Based on the energy transfer of the whole vehicle， a preliminary parameter matching method is developed to meet the performance design target. By establishing the simulation model in Cruise and the vehicle control strategy in MATLAB， the Cruise-MATLAB/Simulink co-simulation is realized， and the rationality of the model is verified. Nonlinear weighted particle swarm optimization （NWPSO） is used to decouple the parameters and realize the global optimization with the vehicle economy as the optimization objective and the coupling relationship among the parameters as the constraints. The results before and after optimization are compared and analyzed by simulation. The results show that the power performance of the whole vehicle is basically unchanged， but the economic performance is improved significantly. The correctness and feasibility of the matching optimization method are verified， which makes the matching of vehicle power system parameters more reasonable.关键词：Pure electric vehicle;Parameter matching;Multi work condition;Cruise-MATLAB/Simulink collaborative simulation;Nonlinear weighted particle swarm optimization algorithm
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发布时间：2022-10-09 - 摘要：When the planetary gear transmission system fails， its signal transmission is coupled with each other， and the nonlinear characteristic is presented， which makes the fault type and damage degree of the planetary gear to be difficultly recognized. The optimization mathematical model of the kernel function scale parameter is constructed by means of Fisher criterion（FC） discriminate function in pattern recognition， and the improved particle swarm optimization method is applied to the optimization to fully improve the analysis performance of the kernel principal component analysis（KPCA） for nonlinear problem. It is applied to the identification and diagnosis of wear damage degree of planetary gear. The results of example analysis show that the intelligently optimized KPCA based on PSO-FC have improve the structure distribution of data in the feature space and achieved the good scale clustering effect in planetary gear wear damage degree recognition. It can effectively solve the identify problems of complex fuzzy damage boundary and damage degree in the mechanical transmission.关键词：Particle swarm optimization（PSO）;Kernel principal component analysis （KPCA）;Planetary gearbox;Damage degree identification;Fisher criterion
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发布时间：2022-10-09 - 摘要：Based on the dynamic measurement method of grating， a set of gear transmission error measurement and data processing device and system are established to realize the precise measurement of gear transmission error. According to the forming process principle， an accurate finite element analysis model including gear assembly error， manufacturing error and modification is created， then the process of simulation test is conducted， and the simulation results and test data are compared to verify the correctness of the finite element model.关键词：Transmission error;Grating;Dynamic measurement;Simulation
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发布时间：2022-10-09
Test·Analysis
- 摘要：Because of the higher viscosity and good thermal stability， the dimethyl silicone oil is considered as a damping fluid for integral squeeze film damper （ISFD）. The influence of damping fluid’s viscosity of ISFD on the vibration reduction characteristics of gear shafts is studied. The mechanical model of ISFD elastic damping bearing system and the damping single-degree-of-freedom vibration system of the gear system are established， which shows the effectiveness of ISFD in vibration reduction of gear shafts. A first-grade spur gear bench is built to compare the vibration of the gear system with rigid support and ISFD elastic damping support with different viscosity damping fluids. Experimental results show that ISFD with a damping fluid of dimethyl silicone oil can effectively inhibit the vibration of gear shafts， and the decline of vibration amplitude is more than 50%. With the increase of viscosity of ISFD damping fluid， the decline amplitude of gear shafts vibration increases. The ISFD with a damping fluid of dimethyl silicone oil has excellent damping vibration attenuation characteristics， which can effectively reduce the vibration of various frequency components and guarantee the smooth operation of the gear transmission.关键词：Integral squeeze film damper （ISFD）;Gear shafts;Dimethyl silicone oil;Damping fluid viscosity;Vibration reduction
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发布时间：2022-10-09 - 摘要：Traditional robot fingers with parallel and self-adaptive hybrid grasping mode have double-chain transmission mechanisms， which have disadvantages of complexity in mechanisms. A novel design of a parallel and indirectly self-adaptive underactuated robot finger with a single chain transmission mechanism， called PISA hand is presented. The method uses three gears， two racks， a slider， a block， a limit and a spring to achieve using a single motor to drive two phalanges. The PISA finger can realized the pinching grasp with the distal phalanx and enveloping grasp with the proximal phalanx with a slider and the distal phalanx. The composition and movement process of the PISA finger are introduced in detail. Theoretical analysis of the range and grasping force are given. Simulation and experimental results show that the PISA finger can automatically switch the grasping modes according to the different positions and shapes of the object so as to achieve stable grasping. The PISA hand has high transmission efficiency， compact structure.关键词：Robot hand;Underactuated hand;Indirect self-adaption;Parallel pinch;Single chain transmission
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发布时间：2022-10-09 - 摘要：Referring to the experimental conditions of a 1.5MW wind turbine gearbox， the simulation is carried out considering the inside and outside dynamic excitation based on the ADAMS platform. Through the debugging of relevant parameters， it is found that the damping coefficient of the supporting rigid body has great influence on the simulation results. In the case of 0.1， the amplitude error of the simulation results and the experimental data at the test point MP1 in the time domain can be controlled within 19.3%， and the main frequency distribution in the power spectrum is much the same. It shows the simulation model after tuning parameter can be exact. Then， the broken tooth fault is implanted in the simulation model and the vibration signals at the measured point are analyzed synthetically in time domain characteristics and Hilbert demodulation. The results are consistent with the theoretic description， which further verify the accuracy of the model. At the same time， it can also be proved that the simulation model and method can play a certain role in the research of vibration characteristics and fault signals of wind turbine gearbox.关键词：Wind turbine gearbox;Dynamics simulation;Vibration characteristic;Fault simulation
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发布时间：2022-10-09 - 摘要：At present， the design and manufacture of the domestic spline cold roll forming machine are mainly based on the experimental data， and theoretical studies are still insufficient. Taking the vertical spline cold roll forming machine for example， the design and analysis methods are studied. Based on the calculation of the forming force， the overall layout and machine tool body structure of vertical spline cold roll forming machine are given. According to the forming force data obtained by simulation as well as the working conditions and force analysis for the sliding table and screw， the key parts of the transmission system are designed. The static and dynamic characteristics of the machine tool are also analyzed by strength and modal analysis for the vertical spline cold roll forming machine.关键词：Spline;Cold roll forming machine;Design;Strength;Modal;Analysis
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发布时间：2022-10-09 - 摘要：In this paper novel measuring methods for profile deviation are proposed based on machine vision. After the tangent point of the basic circle and the normal line of the tooth profile through a sampled point are obtained， angles of vectors determining by the tangent point and the discrete points of the corresponding theoretical involute are obtained. Then the intersection point between the normal line of the tooth profile through a sampled point and the theoretical involute is obtained by using the operations of "comparison" and "XOR". Finally profile deviations are measured in the normal direction of the profile involute， which makes the tested results be consistent with its definitions. In the experiment， the obtained profile deviation is 6.944 3 μm， which demonstrates the proposed method of profile deviations test based on machine vision can meets the need of precision in engineering practice.关键词：Machine vision;Involute;Modulus;Tooth number;Profile deviation
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发布时间：2022-10-09
Development·Application
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